Middlesbrough boss Chris Wilder says goalkeeper Joe Lumley's error for Hull City's winner on Saturday was just one of a number of disappointing mistakes made right through the side.
Boro, who are in the clutch of teams fighting for the play-offs, missed the chance to go back into the top six.
It was a second 1-0 defeat for the Teessiders in the space of four days, after last Wednesday's loss to Fulham.
"I've protected Joe, but that's a mistake," Wilder told BBC Radio Tees.
"He has to save it, there's no hiding place out there.